Threatened fishes of the world: Parachondrostoma turiense (Elvira, 1987) (Cyprinidae)

Abstract

Common names: Madrija (Spanish). Turia Nase (English). Conservation status: IUCN: Endangered [EN B2ab (i,iii,v), Crivelli 2006]; Spain: Endangered (EN B1+2c, Doadrio 2002). Identification: D III+8, A III+9, V II+8, P I+13-14, pharyngeal teeth 6-6 or 6-5, LL 44-51, gill rakers 21-27. Reaches 250 mm SL. A slender-bodied fish, with small head and blunt rounded snout. The mouth is ventral, arched from below, with a thin horny layer on the lower lip. Illustration by B. Elvira. Distribution: Restricted to the Turia and Mijares river basins in eastern Spain (Elvira 1987). Abundance: A rare species continuously declining in numbers and areas occupied (Crivelli 2006). Habitat and ecology: A rheophilic fish living in stretches with swift current, rich in submerged plants (Crivelli 2006). Reproduction: Moves in March-May to upper parts of rivers for spawning, which takes place in schools on gravel bottom (Kottelat and Freyhof 2007), laying 800–1,000 eggs that hatch in 5 days. Threats: The scarce populations are threatened by the introduction of exotic predatory fish, mainly largemouth bass Micropterus salmoides; agricultural pollution; water extraction, and drought (Elvira 1995). The extent of occurrence is less than 5,000 km. Conservation action: Protected at a regional level since 2004. Included in annex III of the Bern Convention and in annex II of the European Directive of Habitats. Two populations of the species are protected by the European Natura 2000 network. Artificial breeding produces about 1,000 juveniles per year which are stocked into the Turia River. Successful natural breeding of released fish occurred in 2008. Conservation recommendations: Effective correction of current threats is necessary. Remarks: Considered a distinct species by Elvira (1997), Doadrio (2002) and Elvira and Almodovar (2008). Doadrio and Carmona (2004) found that P. turiense showed a genetic divergence of 1.6–2.1% with respect to P. arrigonis, and of 1.1–1.3% with respect to P. miegii.